radeonsi: disable sdma for gfx10

Disable sdma on gfx10 until all timeouts bugs are fixed.

See:
    https://gitlab.freedesktop.org/mesa/mesa/issues/1907
    https://bugs.freedesktop.org/show_bug.cgi?id=111481

Reviewed-by: Marek Olšák <marek.olsak@amd.com>

src/gallium/drivers/radeonsi/si_pipe.c

@@ -483,7 +483,13 @@ static struct pipe_context *si_create_context(struct pipe_screen *screen,
 	if (!sctx->ctx)
 		goto fail;
 
-	if (sscreen->info.num_sdma_rings && !(sscreen->debug_flags & DBG(NO_ASYNC_DMA))) {
+	if (sscreen->info.num_sdma_rings &&
+	    !(sscreen->debug_flags & DBG(NO_ASYNC_DMA)) &&
+	    /* SDMA timeouts sometimes on gfx10 so disable it for now. See:
+	     *    https://bugs.freedesktop.org/show_bug.cgi?id=111481
+	     *    https://gitlab.freedesktop.org/mesa/mesa/issues/1907
+	     */
+	    (sctx->chip_class != GFX10 || sscreen->debug_flags & DBG(FORCE_DMA))) {
 		sctx->dma_cs = sctx->ws->cs_create(sctx->ctx, RING_DMA,
 						   (void*)si_flush_dma_cs,
 						   sctx, stop_exec_on_failure);